In recent years, hard disk drives which have been used in diversified applications such as personal computers and portable music players have been demanded to have a higher recording memory, and discs of smaller in size and lighter in weight. With the trends, especially, the recording densities of the recording media that have been used in hard disk drives have dramatically increased over the last five years, and the demands for cleanliness of the substrate surface have become very strict. Therefore, foreign substances, such as soils from oily components and fine particles, on a substrate surface have been demanded to be sufficiently cleaned.
In addition, in the field of semiconductors, especially, high integration and high speeds have been dramatically progressed during the recent 5 years or so. In the production steps of a semiconductor, if a pattern formation using a lithography step is performed on a photomask still having foreign substances, the circuit patterns as designed cannot be obtained, so that troubles such as wire defects are generated, whereby possibly causing worsening of qualities and lowering of production yields. The higher the degree of integration of the semiconductor element and the finer the circuit patterns, the more notably exhibited the tendency as described above. Therefore, in order to suppress worsening of qualities and lowering of production yields of the manufactured article due to the finer formation of the circuit patterns, it has been desired that foreign substances, such as soils from oily components and fine particles, on a surface of a photomask are sufficiently cleaned.
Furthermore, even in flat panel displays (which may be referred to herein as “FPD”) represented by liquid crystal televisions and plasma televisions that have been rapidly growing in penetration rate in recent years, especially during the last five years or so, the degree of cleanliness required for the surface of the panel during the production steps has been increasing, with the advancement in the large-screened, and high-fineness panel sizes.
In view of the situations of the recent years as described above, cleanability of a cleaning agent composition which has been developed based on a technological situation of nearly 10 years before or even before that, for example, the cleaning agent compositions described in Patent Publications 1 to 3 is insufficient for obtaining the required surface quality.    Patent Publication 1: JP-A-Hei-5-43897    Patent Publication 2: JP-A-Hei-11-116984    Patent Publication 3: JP-A-Hei-11-181494